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188 Datasets, Page 1 of 19
American lobster (Homarus americanus) abundance and biological characteristics collected from SCUBA dive surveys in the Bay of Fundy from 1982-2021
This dataset reports on lobster abundance and individual biological characteristics (size, sex, shell hardness, egg status), along with seabed substrate information, collected at various coastal sites in the Bay of Fundy, Canada. Surveys were conducted over a 40-year period between 1982 and 2021. Survey areas and SCUBA dive sites were located around Grand Manan Island, Deer Island, Campobello Island, and along the Bay of Fundy’s New Brunswick shore stretching from Passamaquoddy Bay, east to Maces Bay. One survey area was located on the Bay of Fundy’s southern shore (Nova Scotia) in the Annapolis Basin (Lawton et al. 1995). The data represent a compilation of SCUBA diving surveys (1003 belt transects) conducted directly by Fisheries and Oceans Canada (DFO) scientific SCUBA divers (1982-2019), or by contracted commercial divers funded in association with outside collaborating organizations; Department of Fisheries and Agriculture (DFA; 1990 – 1993), the Grand Manan Fishermen’s Association (GMFA; 2013-2015), and the University of New Brunswick (UNB; 2019-2021).Cite this data as: Lawton P, Dinning K, Rochette R, Teed L. American lobster (Homarus americanus) abundance and biological characteristics collected from SCUBA dive surveys in the Bay of Fundy from 1982-2021. Published August 2024. Coastal Ecosystems Science Division, Fisheries and Oceans Canada, St. Andrews, N.B.For additional information please see:Campbell, A. 1990. Aggregations of berried lobsters (Homarus americanus) in shallow waters off Grand Manan, eastern Canada. DFO Can. J. Fish. Aquat. Sci. 47: 520-523.Denton, C.M. 2020. Maritimes Region Inshore Lobster Trawl Survey Technical Description. DFO Can. Tech. Rep. Fish. Aquat. Sci. 3376: v + 52 p.Lawton, P. 1993. Salmon aquaculture and the traditional invertebrate fisheries of the Fundy Isles region: habitat mapping and impact definition: Cooperation Agreement on Fisheries and Aquaculture Development. Submitted by Peter Lawton to the New Brunswick Department of Fisheries and Aquaculture, 84 p. Unpublished monograph. Available from Fisheries and Oceans Canada Library, Dartmouth, NS (Monographs: SH 380.2 .C2 .L39 1992).https://science-catalogue.canada.ca/record=3943769~S6Lawton, P., Robichaud, D.A., and Moisan, M. 1995. Characteristics of the Annapolis Basin, Nova Scotia, lobster fishery in relation to proposed marine aquaculture development. DFO Can. Tech. Rep. Fish. Aquat. Sci. 2035: iii + 26 p.Lawton, P., Robichaud, D.A., Rangeley, R.W., and Strong, M.B. 2001. American Lobster, Homarus americanus, population characteristics in the lower Bay of Fundy (Lobster Fishing Areas 36 and 38) based on fishery independent sampling. DFO Can. Sci. Advis. Sec. Res. Doc. 2001/093.Wentworth, C.K. 1922. A Scale of Grade and Class Terms for Clastic Sediments. The Journal of Geology 30(5): 377-392.Dinning, K.M., Lawton, P., and Rochette, R. 2025. Increased use of mud bottom by juvenile American lobsters (Homarus americanus) in Maces Bay and Seal Cove, Bay of Fundy, after three decades of population increases and predator declines. Canadian Journal of Fisheries & Aquatic Sciences 82; https://doi.org/10.1139/cjfas-2023-0312
Multidisciplinary winter survey for assessing groundfish in the northern Gulf of St. Lawrence (MV Gadus Atlantica 1978 - 1994)
Fisheries and Oceans Canada (DFO) conducted a winter multidisciplinary scientific surveys with a bottom trawl the northern Gulf of St. Lawrence and Cabot Straight from 1978 to 1994. The specificities of the missions onboard the MV Lady Hammond are described below.Objectives:1. Assess groundfish populations abundance and condition2. Assess environmental conditions3. Conduct a biodiversity inventory of benthic and demersal megafauna4. Collect samples for various research projectsSurvey descriptionThis winter survey covers the northern Gulf of St. Lawrence, that is the divisions 4R, 4S and 3Pn of the Northwest Atlantic Fisheries Organization (NAFO). A stratified random sampling strategy is used for this survey and the fishing gear used on the MV Gadus Atlantica is an Engel 145 Otter trawl. Standard trawling tows last 30 minutes, starting from the time the trawl touches the sea floor. Towing speed is 3.5 knots.DataFor each fishing tow, the catch is sorted and weighed by taxa; individuals are counted and biological data are collected on a subsample. For fish, crab and squid, size and weight are measured by individual and, for some species, sex, gonad maturity, and the weight of certain organs (stomach, liver, gonads) are also evaluated. The soft rays of the anal fin are counted for redfish and otoliths are collected for Greenland halibut and Atlantic cod. Invertebrates are weighted and counted (no individual measurements).The biological data are divided into 4 files: a “Metadata” file containing set information, a “Catches” file containing catches per set for fish taxa, a “Carbio” file containing morphometric measurements per individual and a “Freql” file containing the length frequency of fish. It's important to note that this is raw data. Only sets considered successful are retained. In each set, all species are kept, with a few exceptions. For more information please contact the data management team (gddaiss-dmsaisb@dfo-mpo.gc.ca).
Mackenzie River Exploratory Fishery 1989-1993; Investigation of the Population Structure of Broad Whitefish (Coregonus nasus) and Biological Analysis and Population Assessment of Northern Pike (Esox lucius), Inconnu (Stenodus leucichthys), and Lake Whitefish (Coregonus clupeaformis)
An exploratory fishery was carried out in the Mackenzie River Delta between 1989 and 1993 at the request of the Inuvik Hunters and Trappers Committee to assess the commercial fishery potential in this area. Data collected during this exploratory fishery was used in two technical reports. Broad whitefish were the target species of this fishery (DFO Technical Report 2180), however other species such as northern pike, inconnu, and lake whitefish were also harvested (DFO Technical Report 2330).Biological data from broad whitefish (fork length, age, gonadosomatic index and instantaneous mortality) were analyzed to assess the impact of an exploratory fishery in the Mackenzie River Delta. The data were collected using variable mesh experimental gill nets and commercial harvesters' 139 mm (5.5”) mesh gill nets. The data suggest that the broad whitefish population might be separated, with larger mature spawners gathering in the main channels prior to spawning and smaller, immature or resting fish staying in side channels away from strong currents. From this analysis we conclude that the size and structure of the broad whitefish population(s) found in this area are stable at the current level of total harvest (commercial and subsistence combined) There may be room for increased harvests but to what level is uncertain.Biological data from northern pike, inconnu, and lake whitefish were analyzed to assess the impact of the fishery on population abundance and structure. All three by catch species support subsistence fisheries in the Mackenzie Delta. lnconnu and lake whitefish migrate substantial distances, crossing land claim borders and are likely fished by a variety of user groups. Northern pike, on the other hand tend to be non-migratory with localized populations that are mainly fished by people living in the near vicinity. A concern was that commercial fishing pressure might reduce the numbers of fish available to subsistence users. Based on trends in size and age frequency, age at maturity, sex ratio, growth rates, and mortality rates, we conclude that inconnu and lake whitefish populations in the Mackenzie Delta have remained healthy and stable at the current harvest levels, however northern pike populations showed a decrease in the proportion of older fish, possibly indicating over-fishing of local stocks. lnconnu and lake whitefish may be able to withstand increased harvest, but to what extent is unknown, given that little reliable information is available on subsistence harvest levels in this region. Increasing harvest levels of pike may be risky and we suggest that a reduction of current commercial harvest quotas be considered.
Survey for the assessment of Unit 2 Redfish (CCGS John Cabot)
Monitoring of Unit 2 redfish by Fisheries and Oceans Canada (DFO) ceased in 2002. Since then, the Atlantic Groundfish Council (AGC, formerly the Groundfish Enterprise Allocation Council [GEAC]) has funded surveys approximately every two years in the area, in collaboration with DFO. Over the years, various vessels and gear types have been used. In 2024, a comparative survey was conducted using the CCGS John Cabot and a fishing industry vessel (the Léry Charles) to develop conversion factors that allow data from the 2020, 2022, and 2024 Unit 2 redfish surveys to be standardized to CCGS John Cabot equivalents. The survey covered the waters off southwestern Newfoundland and eastern Cape Breton, corresponding to redfish management Unit 2, which includes NAFO subdivisions 3Pn, 3Ps, 4Vn, 4Vs, and 4W. Here, data collected aboard the CCGS John Cabot are presented. Objectives• Assess the abundance and condition of groundfish and invertebrates• Assess environmental conditions• Inventory the biodiversity of benthic and demersal megafauna• Monitor the pelagic ecosystem• Collect samples for various research projectsData The CCGS John Cabot employed a four-sided modified Campelen 1800 shrimp trawl, fitted with a Rockhopper ("bicycle") footgear. The trawl extension and codend were lined with 12.7 mm knotless nylon mesh. Standard trawl tows were 15 minutes in duration, timed from bottom contact, with a target towing speed of 3 knots.For each fishing tow, the catch is sorted and weighed by taxa; individuals are then counted and biological data are collected on a subsample. For fish, crab and squid, size and weight are measured by individual and, for some species, sex, gonad maturity, and the weight of certain organs (stomach, liver, gonads) are also evaluated. The soft rays of the anal fin are counted for redfish, and the otoliths are sampled for several species such as Atlantic cod, Atlantic halibut, and Greenland halibut. Roughly 2-kg of shrimp are sorted and weighed by species. The other invertebrates are counted (no individual measurements) and photographed.The biological data are divided into 4 files: a “Stations” file containing set information, a “Catches” file containing catches per set for fish taxa, a “Carbio” file containing biological and morphometric measurements per individual and a “Shrimps” file containing information on shrimp catches. The columns source_info, no_survey, nbpc and set_number serve as a common key linking the four datasets.It is important to note that this is raw data. Only sets considered successful are retained. In each set, all species are kept, with a few exceptions. Data is available from 1997-2022 but please contact the data management team (gddaiss-dmsaisb@dfo-mpo.gc.ca) for access and further details. For any other information please also contact the data management team.
Benthic Habitat Mapping Database
The purpose of the survey is to document and record habitat types and associated algae and marine invertebrate species in a variety of habitat types. Transect locations are randomly selected throughout the study area, which rotates between the north and south coasts of British Columbia on a biannual basis. Transects are laid perpendicular to the shoreline. A team of two divers swim the transect with data sheets to collect habitat, algae and marine invertebrate data as detailed below in the methods section. Data is keypunched in an MS Access database that can be queried for species observations and environmental information.This dataset includes three tables pulled from the original database containing observations by species, observations by quadrat, and additional header information for each observation. All three tables can be linked by the field HKey. Three lookup tables are included as well, one for algae, one for invertebrates, and one for substrates.
Multispecies Dive Pilot Surveys
The Department of Fisheries and Oceans (DFO) Science Branch has designed a multispecies dive survey protocol to provide unbiased, coast wide monitoring of benthic invertebrate stocks (as may be required under the updated Fisheries Act) and associated habitat information for a suite of benthic marine invertebrate species (Green (Strongylocentrotus droebachiensis), Purple (S. purpuratus) and Red Sea Urchin (Mesocentrotus franciscanus), Geoduck (Panopea generosa), Giant Red Sea Cucumber (Apostichopus californicus), Northern Abalone (Haliotis kamtschatkana), and Sunflower Sea Star (Pycnopodia helianthoides)). Based on information available at this time, the proposed survey design can provide estimates of coast wide stock status for Red Sea Urchin and Giant Red Sea Cucumber, and relative abundance indices for Geoduck, Green Sea Urchin, Purple Sea Urchin, Northern Abalone and Sunflower Sea Star.The new protocol was tested through a series of pilot surveys conducted on a subset of areas of the BC coast each September from 2016-2021. Design of the pilot surveys was based on previous dive survey data and experience and demonstrated the practical feasibility of the protocol, while also gathering preliminary information to guide recommendations about the statistical design of the survey.The dataset consists of a relational database containing tables representing each component of the survey methodology. The primary component of the survey is a transect location. Along each transect, systematically spaced quadrats are sampled, and on each quadrat, substrate observations are recorded, multiple species of algae are recorded, and multiple individual invertebrates are measured or counted. The tables are linked by transect number and quadrat number.
Provincial Sanctuary - Corridor Wildlife
The Provincial Sanctuary - Corridor Wildlife dataset is comprised of all the polygons that represent the Provincial Sanctuary - Corridor Wildlife areas in Alberta. Provincial Sanctuary - Corridor Wildlife is area designated for the protection of wildlife within 400 yards corridors of various road centre-lines.
Cobb Seamount Visual Survey 2012 (ROV)
This dataset contains observations of species occurrences from seafloor imagery collected by the remotely operated underwater vehicle (ROV) during the 2012 Expedition to Cobb Seamount. The ROV operated by Fisheries and Oceans Canada was a customized Deep Ocean Engineering Phantom HD2+2 which collected photographic images from 12 transects ranging from 35 m to 211 m in depth.
SCUBA Surveys to Assess Lobster Population Structure and Density in the Southern Gulf of St. Lawrence
PURPOSE:The SCUBA survey was designed to assess the density of small lobsters (1-3 years of age) in rocky reefs, in the nearshore habitat.DESCRIPTION:Total number of transects surveyed and total number of lobsters measured for each site in each year. There are some sites that do not have any coordinates identified, therefore these have not been included in the Web Map Services (WMS). PARAMETERS COLLECTED:size measurement (biological); species counts (ecological); substrate (geological)SAMPLING METHODS:Transects are laid-out from a small vessel using buoys, anchors, and a 100 m leaded rope along the bottom, marked at 5 m intervals. A strip transect survey method is used whereas two divers sample a 1 or 2 m strip (dependent on lobster density) alongside either side of the leaded rope. All captured lobster are measured (carapace length) and all lobsters of ≥20 mm carapace length are sexed. The complexity and suitability of the habitat is assessed in the 5 m sections (e.g. rocky reefs, sand, large boulders).USE LIMITATION:To ensure scientific integrity and appropriate use of the data, we would encourage you to contact the data custodian.
Demersal fish and benthic invertebrate assemblages in the Northwest Atlantic
Marine classification schemes based on abiotic surrogates often inform regional marine conservation planning in lieu of detailed biological data. However, theses chemes may poorly represent ecologically relevant biological patterns required for effective design and management strategies. We used a community-level modeling approach to characterize and delineate representative mesoscale (tens to thousands of kilometers) assemblages of demersal fish and benthic invertebrates in the North-west Atlantic. Hierarchical clustering of species occurrence data from four regional annual multispecies trawl surveys revealed three to six groupings (predominant assemblage types) in each survey region, broadly associated with geomorphic and oceanographic features. Indicator analyses identified 3–34 emblematic taxa of each assemblage type. Random forest classifications accurately predicted assemblage dis-tributions from environmental covariates (AUC > 0.95) and identified thermal limits (annual minimum and maximum bottom temperatures) as important pre-dictors of distribution in each region. Using forecasted oceanographic conditions for the year 2075 and a regional classification model, we projected assemblage dis-tributions in the southernmost bioregion (Scotian Shelf-Bay of Fundy) under ahigh emissions climate scenario (RCP 8.5). Range expansions to the north eastare projected for assemblages associated with warmer and shallower waters of the Western Scotian Shelf over the 21st century as thermal habitat on the rela-tively cooler Eastern Scotian Shelf becomes more favorable. Community-level modeling provides a biotic-informed approach for identifying broadscale ecolog-ical structure required for the design and management of ecologically coherent, representative, well-connected networks of Marine Protected Areas. When com-bined with oceanographic forecasts, this modeling approach provides a spatial tool for assessing sensitivity and resilience to climate change, which can improve conservation planning, monitoring, and adaptive management.Cite this data as: O'Brien, J.M., Stanley, R.R.E., Jeffery, N.W., Heaslip, S.W., DiBacco, C., and Wang, Z. Demersal fish and benthic invertebrate assemblages in the Northwest Atlantic.Published: December 2024. Coastal Ecosystems Science Division, Maritimes region, Fisheries and Oceans Canada, Dartmouth NS.https://open.canada.ca/data/en/dataset/14d55ea5-b17d-478c-b9ee-6a7c04439d2b
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